This is a supplement to National Cancer Institute grant DHEW 2 RIO CA 11233. This supplementary request is for three research assistants. These individuals have been providing care for our patient population and have allowed us to complete our clinical protocol studies. The primary object of this project is to conduct clinical research in pediatric cancer, with emphasis on chemotherapy, to thereby raise the cure rate in children with malignant disease, and to provide maximum disease control in those not cured. Research activities in chemotherapy will be structured around participation of our Pediatric Oncology Team in a cooperative group, the Southwest Cancer Chemotherapy Study Group (SWCCSG). This six-member team comprises three pediatric chemotherapists, two pediatric surgeons, and one radiotherapist. All are associated with the SWCCSG. At the University of Oklahoma, most of our clinical studies (78 percent) are Phase III in acute leukemia. Phase III in solid tumors accounted for another 10 percent, and the remainder were Phase II and I acute leukemia and solid tumors. Phase I studies account for less than 1 percent of our case entries into SWCCSG protocols. Oklahoma will enter cases into at least 24 different SWCCSG protocols.